Safety device



oct. 25,1927. 1,646,971

J. c. MENDONCA SAFETY- DEvxcE Fild Dee. 51, 192e s sheets-sheet 2 2" .01ze @y JM/vendio@ JMendonca 1,646 971 Oct' 25 1927 J. c. MENDONCA SAFETYDEVICE Filed Dec. 5l, 1926 3 Sheets-Sheet 3 ffnung Patented Oct. 25,1927.

UNITED S'illia'ih PATENT FFICE.'

SAFETY DEVICE.

Application led December 31, 1925. Serial No. 158,380,

The invention has for an object to provide a device adapted to bereadily installed on engines of various types for use to positivelyprevent accidental operation of the engine from any cause whatever, suchas a leaky throttle, casual opening of the throttle, loosening of thebrakes while the engine or train is on a grade, or other causes tendingto cause the train to move alone.

It is a further important purpose to provide such a device which will beapplicable to use in emergency as a train stopping means. In thisconnection it is an aim to give a desirable mechanism whereby the actionof the device will be synchronized with the engine action wherebypositive operation is assured regardless of the position of the enginepart-s when a controlling device is operated. This particular embodimentof the invention aims to present a chock or locking member movable to beinterposed between the cross head of the piston rod, and the adjacentcylinder-head or adjacent framing, with means cooperative with the'cross head at will to cause locking of the engine mechanism.

It is an important aim to enable the operation or control of the devicewith ay minimum of physical effort and in an extremely simple manner.

A further purpose is to enable the construction ofsuch a device in avery compact form, so that it may be accommodated to spacealreadyavailable, without modification of customary engine construction, andwithout projections extending to an undue distance laterally.

Additional objects, advantages and features of invention will appearfrom the construction, combination and arrangement of parts hereinafterset forth and shown in the drawings, in which Figure 1 is a sideelevation of an engine equipped with my invention.

Figure 2 is a top `view thereof.

Figure 3 is an enlarged detail view of the cross-head guide and adjacentparts, including the locking mechanism, with resetting parts removed.

Figure 4l is a top view of the parts in Figure 3.

Figure 5 is a cross section centrally of Figure 3 looking forward.

Fig-ure 6 detail of a latch lifter.-

Figure 7 is a side view showing the mechanism in position.

Figure 8 is ai cross section centrally of Figure 7.

Figure 9 is a detail of the detent.

There is illustrated an engine 10 of a standard type now in use,including a cylinder head 11, cross head guide 12, piston rod 13, crosshead 14 connected thereto and operable in the guide 12, and theconnecting rod 15 pivoted in the cross head, these elements being of thecustomary construction. The cross head guides are supported kby theusual guide yoke 16. Slidably engaged with the respective guide bars ofthe cross head guide there are upperl and lower sliding blocks 17 and18, the latter carrying three horizontal laterally projected guideboltsal middle one 19 and two end ones 20. The upper block 17 has asingle horizontal bolt 21, similar to and alined vertically with andover the one 19. A frame piece 22 is in the Vform of an invertedT-apertured` at each end of its stem and at the outer ends of theybolt-s 19 and 21 there `are engaged helical springs 23 confined betweenthe frame piece 22 and the heads of the bolts, by which the frame pieceis pressed forcibly inwardly against the blocks 17 and 18. Twohorizontal arms 211 are formed on the inner side of the stem of theframe piece 22, one above and the other below the piston rod, and proijecting beyond a vertical plane coincident with the axis of theA rod.Carried by each of these arms there are two horizontal shafts 25,parallel to the piston rod and on opposite sides thereof, around theends of each of nient of the block under presente of 'the to seat snuglythereagainst at thesaine time. The length of the bolts 19-20-21 is suchas to permit the outward movement of -thepiece 22 until lthe blocks 27clear theV path of the'cross head, and it is normally so held againstthe action of the springs 23 by a detent yoke 31, including a centrallyApivoted lever portion 32 carried by a suitable exten-l sion of theblock 17. The yoke fits snugly around the bolt, bearing both against theblock 17 and the frame piece 22. The lever portion Vincludesan'operating arm 33 extending rearwardly, and arranged to be engaged anddepressed by 'a rocker arm 34 when .moved forwardly, for lifting of theVyoke and inward movement of the piece 22 ,under action of the springs23.

` proper and the arm 33 may be fixed on 0pposite ends Vof a shaft 35i'evolubly mountedV 0n the block 17, as shown. The rocker armV issimilarly mounted on Vthe inner end ofa shaft 36 also revolubly mountedon'the block 17, the outer end-ofwhich hasiixed Ythereon asimilar arm 37extending downwardly and 'engaged by a contractile spring 38"attachedtothe `bracketplate 16, and tending todraw Y *the arm rearwardly. i Thearms-34 and 137 arejheld against this movement normally by means of a`detent deviceV 39 mounted on the yoke 16 and adapted to engageand holdthe'4 arm 34k at the rearmost limit yof its .move- .nient7 and beingreleasable by al link 40, Vbell crank.,41, rod 42 and connected level'43 in the engine cab 44, as will be described. AV

latch bill-45 is mounted pivotally on the shaft' 36, adapted whenYlowered to engage over the Vupper edge of the plate 16 andhold theblocks 17 and 18 against sliding movement on the cross head guides. Onthe shaft 136 `there is `fixed a shouldered collar-46, the

shoulder'46 of whichfis arranged so as toA strike'the latch at a certainpoint in the forward movement of the arm 34 and lift the' latch. Thearm'37 is'of sufficient radius V'and spaced outwardly `ofthe guide bars12 enough toengage a striker block'47 on the outer side'of the crosshead,'this vblock being yinclined at fits rear part as at 48. The.

i y spring 38 is connected to a lug 50 on theside :of the'arm 37,wherebyzwhen the detent) is released the'earin 37 will be drawn rear-Vwardly` to the position shown inFigure 7.

This armis of such-length as to Vswing into :thepath'fof thezblock 47,and tendsto remain in this path so that rearward movement of the block47 f will swing the arm 37 with The yoke ithe engine cab `44 and it, theinclined face 48 fending the arm upwardly until the block may passthereunder. The block is of a length teclear the arm entirely in itsrearward movement until the return of the crosshead under resetting ofthe device as will be described.4 The movement of the arm 37 rotates theshaft 36, and causes the arm 34 to bear downwardly on the arm 33 of the.member 31 and permits inward movement of the frame piece 22 so thatforward vmovement of the crossliead is checked. By means of asuitablespringf the members 17 and^18 are held at'th'e rear limit oftheirinoveinent, so that upon the rotation of the shaft 36 to initialposition, thel latch 45 will engage over theV bracket plate 16 holdingthe parts against loose movement on. the crosshead guide. The detent '39coinprises a lug 54 on the yoke l16, having a crank dog 55 pivotedthereon, fthe pivot axis being within thera'dius ofthe arm 34.

vThe dog has an eccentric block 57 Y projectingY across the path of thearm 34, and borne into thepath of the arm by a spring 58 seated againstthe bracket 16, a check lug 59 being 'formed on the'lug 54 to limit themovement `of the dogby: the spring.: The dog has also a crank arm andwrist 60, the latter being engaged in the slotted end of a: link 40, the

upper end of which isV connected toaii'outV lwardly projecting arm onthe rod 42 connected thereto, the latter being extended into `connectedto a suitable operating lever 43.

through the stem of the frame piece 22. The yoke is provided with astem64 extend- Ving upward and I'inclined Vinward slightly when thedevice is in released position, 'and carried on the i'od 42 there isan'arin` 68 at the forward end of which there .is fixed the elongatedYcrank 'pin 'orv stub shaft 6.9 movable in an are of such'radiusthat it`will strike thearm 64 when the blocks 17 land 18 are at either limitoff their movement, thus "inovngthe frame piece 22 outwardly andremoving Vthe impediment from the pathof the piston cross hea-d.'V ltlisonlynecessary for the engineertoinoveA the lever .43 to Yinitialposition 'while lie-opens the throttle and moves the: piston to theforward limit i of its movement. 4ln order to permit operaftion ofthelever 43it maybefnecessaryiiirst toinove the erosshead to rearinostposition,

depending upon thecircunistances attending thefreleasei of the devicepreviously.

In use, the device may be usedas a safety appliance on standing enginesto prevent casual operation of the train,'and 'it should be arequirement thatthe device is toi-be released whenever a terminal isreached, or

Foijfresetting the device therefis Vpivo'tedr on the block 17abifui'cated lever yoke 61 carried'by Vsuitable bracket arms 62 on the:block 17,theextremities of the furcations Acarrying revolubly a shortshaft 63 engaged when a stop of more than a predetermined duration is tobe made, and whenever the engineer leaves the cab. The device may bereleased quietly by use of the lever 61 when the cross head is atreal-most position.

ln case ot emergency it is only necessary to move the lever a?) tooperate the detent, and the blocking action will not occur until thecrosshead is in proper position for etieient operation of the device.The lever t?) should be arranged so that it will remain in. releasedposition, and it desired any suitable means may be provided whereby itwill tend to moveto released position and will be held in set positionby a detent, the release of which will cause automatic operation ot thedevice.

In emergency action, or' whenever the engine tends to move when thedevice is in released position, if the crosshead is at an intermediateor forward position, as soon as the detent 39 is operated, the springmoves the arm 34 forwardly until. near or against the arm 33, butwithout suiiicient force to lift the detent yoke 31. The arm 37 has thenfallen into the path oi the block 17, and the rearward movement oli theblock will move the arm 34: with suilicient force to lift the yoke 31just after the cross head has cleared the path of the blocks 27 whenmoved inwardly. The connecting rods are then on dead center at therespective sides ot the engine, and the springs 26 and 53 will allow thecross head to move forwardly approximately halt a stroke undersutlicient pressure, the 'frame piece 22 and blocks 17 and 18 beingcarried therewith part way. The cross head will be checked at a pointwhere resistance to the rotation of the drivers of the engine may beexerted with the maximum etliciency, the resilient action of the springs2G serving to reduce the shock and minimizing the liability of -fractureof the main rod 1 5.

I claim:

1. In a locomotive, the combination oit a reciprocating power member, alined element, a member movable into the path of the reciprocatingmember between said reciprocating member and the fixed element, means tomove the movable member, and means to hold the movable member ininoperative position at times.

2. In a locomotive, the combination of a crosshead guide and cross headand supporting means therefor, a blocking device movably mounted on thesupporting means for engagement in the path of the cross head at times,means tending` to move the blocking device into engaged position,releasable means to hold the blocking device in disengaged position, andmeans to release the last named means.

3. A device oit the class described comprising a cylinder element, across head operatively associated therewith, a support, anelemeiit-movably mounted thereon including members movable into the pathot the cross head, and means to ope-rate said movable element.

4l. A device of the class described comprisino` a cylinder element, across head operatively associated therewith, a support, a movableelement thereon including blocking means movable into the path ot' thecross head, yieldable means engaged with and tending' to move themovable' element into blocking posit-ion, a dote-nt normally engagefltherewith to hold the movable element in inoperative position, detentreleasing means cooperative with the cross head to move the detent outot engagement when said releasing means is in a predetermined relationto the orosshead, means to move the releasing means into suoli relation.and means to hold it out ot' such relation.

5. A device of the class described comprising a cross head guide andsupporting framing, a crosshead reciprocable therein, a blocking devicemovable into the path of the crosshead including longitudinally spacedelements, a cushioning device therebetween, and means to operate theblocking device.

6. A device of the class described comprising a cross head guide andsupporting framing, a cross head reciprocable therein, a longitudinallymovable support on the guide, a blocking device carried thereby movableinto the path of the crosshead including longitudinally spaced elements,a cushioning device therebetween, and means to operate the blockingdevice.

7. A device of the character described comprising a cross head guide andsupporting framing, a cross head reciprocable therein, a longitudinallymovable support on the guide, a blocking device carried thereby movableinto the path of the cross head including longitudinally spacedelements, a cushioning device therebetween, yieldable means engaged withand tending to move the blocking device into blocking position, a detentnormally engaged therewith to hold the blocking device in inoperativeposition, detent releasing means cooperative with the cross head incertain positions of the releasing means to move the detent out ofengagement, means to move the releasing means into one of said certainpositions, means to hold it out et such positions, and a check device tohold said longitudinally movable support at a predetermined limit of itsmovement, cooperative with the said detent releasing means to releasethe longitudinally movable support.

8. A device of the class described comprising a cross head guide, andsupporting framing, a crosshead reciprocable therein, a movable supportreciprocable on the guide, a laterally reciprocable frame piece carriedby ltll) the movable support, including an inwardly projected partarranged to Vengage across the path of the cross head when the framepiece is at the inner limit of its movement, at least one horizontalshai't carried by the Y inwardly projected part, longitudinally re- Yiociprocable members thereon on opposite sides of the frame piece andoutwardly of the ends ofthe shaft, means-to limit their outward movementon the shaft, resilient means active thereon Vto bear them outwardly,and means to operate the frame piece for the purposes described.

l `9. A device of the class describedV comprising a crosshead guide andsupporting means including' an end piece across one end, a cross headreciprocable in the guide, a movable support reciprocable on the guide,means to hold the movable support in initial position at times, ablocking device engageable with the crosshead at times, means tending tooperate the blocking device cooperative with the crosshead when in apredetermined relation thereto and means `on the supporting tooperatetthe movable member'including cabfcontrolled devices.V Y

'In testimony whereof I affix my signature.

. JOHN C. MENDONCA.

